Tillerson, making his first trip to Africa as the senior-most US diplomat, has visited Ethiopia, Djibouti and Kenya since last Wednesday.

World Bulletin / News Desk

US Secretary of State Rex Tillerson on Monday was to shorten his maiden tour of Africa because of work, aides said.

"Due to demands in the secretary's schedule he is returning to the US one day early, after concluding official meetings in Chad and Nigeria," Undersecretary of State Steve Goldstein told the press.

He is due to fly from the Chadian capital of N'Djamena on Monday to the Nigerian capital Abuja, staying there for several hours before heading for home in the early evening.

He had initially been scheduled to stay there overnight, hold further meetings on Tuesday with US embassy staff and then fly back to Washington.

But the African tour has coincided with the shock announcement of a possible summit between North Korean leader Kim Jong Un and US President Donald Trump over the nuclear standoff in the Korean peninsula.

Tillerson, while in East Africa, cancelled scheduled events on Saturday on the grounds of ill-health.

"The secretary is not feeling well after a long couple days working on major issues back home such as North Korea and has cancelled his events for the day," Goldstein said in a statement on Saturday.

He later said Tillerson was "feeling better" and would resume his schedule on Sunday.